Substituted hydroxylamine anti-oxidants

ABSTRACT

Substituted hydroxylamines exhibit activity as anti-oxidants for a diverse group of substrate materials under specific conditions of exposure to an oxidizing environment. Illustrative embodiments of substituted hydroxylamine anti-oxidants are bis(pnitrobenzyl)hydroxylamine and 2-diethylamino-4,6,-bis(N-n-propylN-hydroxyamino)-s-triazine.

United States Patent [1 1 Klemchuk 1 Feb. 18, 1975 4] SUBSTITUTEDHYDROXYLAMINE ANTl-OXIDANTS [75] Inventor: Peter Klemchuk, YorktownHeights,

[73] Assignee: Ciba-Geigy C0rp0ration,Ardsley,

[22] Filed: Oct. 10, 1972 [2]] Appl. No.: 296,447

Related US. Application Data [62] Division of Ser. No. 133,700, April13, 1971,

' abandoned.

[56] References Cited UNITED STATES PATENTS 3,287,125 11/1966 Green eta1. 260/561 A X 3,778,464 12/1973 Klemchuk 260/561 A X PrimaryExdminer-Lewis Gotts Assistant Examiner-Ethel G. Love Attorney, Agent,or Firm-Nestor W. Shust [57] ABSTRACT Substituted hydroxylamines exhibitactivity as antioxidants for a diverse group of substrate materialsunder specific conditions of exposure to an oxidizing environment.Illustrative embodiments of substituted hydroxylamine anti-oxidants arebis(p-nitrobenzyl)hydroxylamine and 2-diethylamino-4,6,-bis(N-n-propyl-N-hydroxyamino)-s-triazine.

1 Claim, N0 Drawings 1 SUBSTITUTED HYDROXYLAMINE ANTI-OXIDANTS DETAILEDDISCLOSURE This is a division of application Ser. No. 133,700, filed onApr. 13, 1971, now abandoned.

The present invention relates to substituted hydroxylamines and moreparticularly to a process for stabilizing a vast and diverse group oforganic materials against oxidation, that is against deterioration inthe presence of air, oxygen or ozone, and to stabilized compositionscontaining said substituted hydroxylamines.

The prevention of oxidation of various organic mate rials is obviouslyof primary industrial concern and therefore anti-oxidants are used in oradded to a wide variety of commercial products such as rubber products,oils, plastics, organometallic products, foods, etc., which are normallysubject to oxidative deterioration.

One group of hydroxylamine anti-oxidants of the present invention isrepresented by the formula wherein R R and R are alkyl, dialkyl amino,monoalkyl amino, hydroxylamine, alkyl hydroxylamino, alkylthio, alkoxy,phenoxy or alkyl phenoxy, the alkyl and alkoxy groups containing from 1to 12 carbon atoms, with the proviso that at least one of R R and R is ahydroxylamine or alkyl hydroxylamino group.

Another group of compounds is represented by the formula wherein R isHON, HONH or HONR wherein R is alkyl or phenylalkyl, the alkyl groupscontaining from 1 to 3 carbon atoms, m and n are the integers l or 2, Xis amino, mono alkylamino, di-alkylamino or alkoxy, the alkyl and alkoxygroups containing from 1 to 12 carbon atoms. 4

A further group of compounds of the present invention is represented bythe formula so, n

NOH

wherein R or R is alkyl containing from l to 3 carbon atoms, benzyl,chlorobenzyl, nitrobenzyl, benzhydryl or triphenylmethyl with theproviso that only one of R; or R is alkyl and that R is hydrogen when R,is benzhydryl or triphenylmethyl, or R and R taken together with thenitrogen atom form a heterocyclic group such as morpholino, piperidinoor piperazino.

The valuable and novel hydroxylamine compounds of the present inventionare prepared by a variety of conventional procedures. In one procedure,cyanuric chloride or a substituted monoor di-alkylaminochloro-s-triazine is reacted with hydroxylamine or alkylhydroxylamine. An alternative procedure involves the reaction of abenzyl halide with hydroxylamine or alkyl hydroxylamine. Anotherprocedure involves reaction of a di-substituted amine thatis, adi-alkylamine, with methyl acrylate to form a tertiary amine which isthen oxidized as, for example, with peracctic acid and the resultingamine oxide is then treated with alkali such as 5 ethyl acrylate, laurylacrylate or acrylamide.

wherein R, is alkyl or phenylalkyl, the alkyl groups con- A furtherprocedure for preparing novel hydroxylamines of the present inventioninvolves reacting a monoalkyl hydroxylamine with a sultone, i.e., acyclic sulfonate ester.

It has been found that the substituted hydroxylamine compounds of thepresent invention are excellent antioxidants and consequently, onincorporating such substances into various organic substances whichundergo oxidative deterioration in the presence of air, oxygen or ozone,there is a surprising and unexpected inhibition of said oxidativedeterioration.

Thus the compounds of this invention are useful as anti-oxidants in awide variety of oxygen sensitive materials. For example, liquidhydrocarbon fuels such as, kerosine fuel oil, etc., are characterized byincreased storage stability by including therein one or more of theoxidants of the present invention. It has been found that liquidhydrocarbon fuels such as gasoline which contain organometallicadditives such as tetraethyl lead as well as other organometalliccompounds which are used as fuel additives exhibit increased oxidativestability by use of the compounds of the present invention. This is alsotrue of lubricating oils and functional fluids derived from naturallyoccurring hydrocarbons such as turbine, hydraulic, transformer and otherhighly refined industrial oils; soaps and greases; plastic materials;synthetic polymers such as polyethylene and polypropylene, etc. Theaddition of small amounts of the compounds of the present invention tothe aforesaid materials greatly increase their resistance todeterioration in the presence of air, oxygen or ozone. Furthermore, suchfuels which contain halogen and phosphorus-containing scavengers for theorganometallic compounds referred to above are also stabilized by theantioxidants of the present invention.

It should also be mentioned that the compounds of the present inventionare also valuable in protecting paraffin and micro-crystalline petroleumwaxes against the oxidative deterioration which leads to rancidity.Furthermore, the compounds of this invention are extremely useful in thestabilization of fats and oils of anima] or vegetable origin whichbecome rancid during periods of storage due to oxidative deterioration.Typical fats and oils include butter fat, lard, beeftallow, fish oilssuch as cod liver oil, as well as various foods containing or preparedin animal fats which tend to deteriorate, i.e., potato chips, friedfish, donuts, crackers and various types of pastry as well as cakes andcookies. Still further, fat fortified animal feeds and fish meals usedas animal feeds are not only protected against oxidative deteriorationby the use of the hydroxylamine compounds of the present invention butin addition, the aforesaid compounds inhibit the degradation of vitaminsA, D and E and certain of the B complex vitamins. The compounds of thepresent invention are also advantageously helpful in compositionscontaining oils derived from vegetable sources such as castor oil,soybean oil, rapeseed oil, coconut oil, olive oil, palm oil, corn oil,sesameoi], peanut oil, babassus oil, citrus oil and cottonseed oils aswell as compositions containing these oils such as peanut butter,peanuts and other whole nuts, salad dressings, margarine and othervegetable shortenings.

Specific hydroxylamines which are useful as antioxidants include, forexample, N,N-dibenzyl hydroxylamine,2-diethylamino-4,6-bis-(N-methyl-N-hydroxyamin)-s-triazine of theformula N (C2H5 A )\NJ\V a OH 7 OH2,4-bis(N-hydroxyamino)-6-diethylamino-s-triazineof the formula CZHE )2A 2,4-bis(dibutylamino)-6-N-hydroxyamino-s-triazinc of the formula NHOH4 Bis-( 3 ,5-di-t-butyl-4-hydroxybenzyl )hydroxylamine of the formula(Ho CH2 )QNOH 2-Octylthio-4,6-bis-N-(hydroxyamino)-s-triazine of theformula SC H1 7 N HNOH H 0H N-hydroxy 2,2,6,6-tetramethyl-4-piperidoneof the formula 2,4-bis-(octylthio)-6-N-hydroxyamino-s-triazine of theformula NHOH A a c li 'l Bis-(p-nitrobenzyl)hydroxylamine of the formulaJQ- CH2)2NOH 2,4-Bis-(dodecylamino)-6-N-hydroxyamino-striazine of theformula IIIC1 H S H2-(N-n-propylhydroxyamino)-4,6-bis-(diethylamino)-s-triazine of theformula B,,B'-Hydroxyimino-bis-(N,N-dimethylpropionamide) of the formulai I HON CH2CH2CN(CH3)2 Experiments have shown that the hydroxylamines ofthe present invention exhibit remarkable radical trapping ability(equivalent to anti-oxidant activity) in tetralin oxidation(tetrahydronaphthalene). For example, it was found that many of thehydroxylamines tested were considerably superior to the phenolicantioxidants in inhibiting the rate of tetralin oxidation during theinduction period. This is indicated by the rates of oxygen uptake duringthe induction periods. Table 1 below sets out a compilation of data ontetralin oxidation tests.

TABLEI Performance in Tetralin Oxygen Uptake Test (C. 2.50 M Tetralin,2.0 X I0 M antioxidant 3.0 X 10 M azo bis isobutyronitrilc,

2-Diethylamino-4,6-his-( N -npropyl-N-hydroxyamino-striazine (L25 lobThe graph below shows a typical plot of oxygen uptake versus time for aninhibited tetralin oxidation. The induction period slope represents ameasure of the radical trapping ability of the anti-oxidant; the lowerthe slope, the more efficient is the radical trapping. It is noted thatthere is a dramatic increase in radical trapping ability whenanti-oxidants are added. Plot of Oxygen Uptake vs Time for HydroxylamineAntioxidant Fig zre 1.

Plot of Oxygen Uptake vs Time for Hydroxylamine Antioxidant Vol. 0

11. Initial Slope Induction Period time c Post-induction Slope dUninhibited Oxidation The length of the induction period is a matter ofstoichiometry, usually two radicals being trapped per antioxidantmolecule. However, deviations from this 2:] ratio are frequentlyobserved, due, presumably, to inhibitor instability or to chemistrywhich is different Ammxidam $933 from the usual. During the postinduction period, the rate of oxygen uptake should be the same as thatfor Benzhydryl hydroxylamine 55 Min. uninhibited tetralm oxidation, butthis IS not always the BMZMichlmbmfl)hydmxylamine 85 case and thereasons for deviations are not known.

Hydroxylamine anti-oxidants have been tested in a f g 98 variety ofrepresentative substrate materials as set out in the following tables.For example, the hydroxylg y q -"-P 'PY amine anti-oxidants perform wellin cyclohexene at y mxyam'm'smazme 183 100C (Table II), in lard at 100C(Table I") and are Bis-(p-nitrobenzyl)hydroxylamine l23 also opgeratrvein mineral 011 (Table IY) and ABS resin 2ABMdodecylamino) 6 N hydmXy at300 F (Table V).'The tests given in Table VI show amino-s-triazine 110that the subject hydroxylamines exhibit a remarkable light stabilizationwhen incorporated in polypropylene.

TABLE lll TABLE II Performance of Hydroxylamine Anti-oxidantsAntioxidant Performance in Cyclohexene, 100C in Lard; 100, 0.05%Anti-oxidant Induction Induction Ami-oxidan P riod Anti-oxidant PeriodHours None 295 min. None 4 Didodec l -h drox imino'di r0 ionate 85 y B By y p p N,N-dibenzylhydroxylamine 48 N,N-Dibenzyl hydroxylamme 78 2Diethylamino 46 biS (N methyl N NhYdmwmorPholine 131hydroxyamino)-s-triazine 32 zmethylaminmli 6 bis (N methyl N2.4-Bis-ldibutylamino)-6-N-hydroxyaminor 1 hydroxyamino)-s-triazine 148S mama Bis-l3,5-di-t butyl-4-hydroxybenzyl) N-hydroxypipendme 57hydroxylamine 75 2,4-Bis-(dibutylamino)-6-N- hydroxyamino-s-triazine ll() Bis-(4-chlorobenzyl)-hydroxylamine 60 TABLE vBis-(3,5-di-tbutyl-4-hydroxybenzyl) hydroxylamine 58 Performance ofHydroxylamine Anti-oxidants M' lO'l, 150 C. 0.17 t'- dBis-(2-chlorobenzyl)hydroxylamine 69 m meta l I an I I d zMonobenzylhydroxylamme 49 Ami oxidam s g2-Dodecylamino4.6-bis-(N-n-propyl-N- hydroxyamino)-s-triazine 103 Nonehours 2-Diethylamino-4 6-bis-(N meth v yl-N- Bis-(2,6-dlchlorobenzyl)hydroxylamine 71 hydroxyamino) s mazine 42 Diethyl B,p' hydroxyiminodipropionate 2ATMdibutyamino) 6'N hydmXyamino Bis-(3,4-dichlorobenzyl)hydroxylamine S'mazme TABLE V HydroxylaminesPerformance in ABS Resin, 300F Carbonyl Values/mil at times indicatedCompound initial 30 min. 60 min. min. minv minv 0.1% Inhibitor None .060.l28 0.22 a a a 2-Diethylamino-4,6-bis- (N-methyl-N-hydroxyamino)-striazine .044 .041 .042 .048 .054 0.089 2,4-bis-(dibutylamino)-6-N-hydroxyamino-s-triazine .047 .080 .l3 .20 a a 0.1% Inhibitor, 5.0%Titanox AMO" None .048 .105 .19 .2l :1 a 2-Diethylamino-4.6-bis-(N-methyl-N-hydroxy amino)-s-triazine .044 .044 .047 .055 .080 0.122,4-Bis-(dibutylamino)-6- N-hydroxyamino-s-triazine .043 .099 0.15 .20 aa awe high to measure accurately analase titanium dioxide TABLEll-Continued Anti-oxidant Performance in Cyclohexene, l00C TABLE VIPerformance of Hydroxylamine Anti-oxidants in Polypropylene 0.5%Antioxidant EXAMPLE 1 2-Octy1thio-4,6-bis-( N-hydroxyamino)-s-triazineHydroxylamine hydrochloride (117.3 g, 1.69 mole) was dissolved in waterand to this solution there was added 62.5 g (1.56 moles) ofa sodiumhydroxide solution, the addition being effected dropwise at atemperature of less than 22. 2-Octylthio-4,6-dichloro-striazine (60 g,0.186 moles) in 180 ml of dioxane was added to this solution, theaddition being effected in a thin stream for a period of about 10minutes at a temperature less than 15. A gummy solid separated after aperiod of stirring. The mixture was warmed to a temperature of between55 and 60, and stirred at that temperature for 1 hour. The mixture wasthen heated at reflux for three hours and then poured into a liter ofwater after cooling. There was obtained a gummy precipitate. Thesolution was decanted and the solid was dissolved in ether. The phaseswere separated and the decanted solution was extracted with ether. Theethereal solutions were combined and washed with water. The etherealsolution was concentrated first at atmospheric pressure to remove theether and finally under vacuum. There was obtained 44.2 g of a pale,purple solid concentrate with a strong odor of octyl mercaptan. Thismaterial was recrystallized from ethyl acetate and there was obtained ayield of 21.9 g of colorless crystals with a melting point of 145-146.5.5

Analysis for C,,H,,N,O,

Calcd.: C, 45.97; H, 7.37; N, 24.37 Found: C, 45.73; H, 7.16; N, 24.16 6

EXAMPLE 2 2,4-Bis-(octylthio)-6-N-hydroxyamino-s-triazine The procedureset out in Example 1 above was fol- 6 lowed except that 58.6 g (0.845moles) of hydroxylamine hydrochloride and2,4-bis-(octylthio)-6-chloros-triazine were used. The reaction wascarried out and at the end of the reaction period, the product wascooled and allowed to stand overnight. Two liquid phases were present.The upper organic phase solidified. The reaction product was poured into1 liter of water, filtered and-washed with water. This was followed bydrying under vacuum and there was obtained a yield of 72 g of productwith a melting point of 87-90. On recrystallization from ethanol, therewas obtained 54.7 g of a product with a melting point of 91 .592.5. Theproduct was recrystallized from ethanol with a charcoal treatment.Product recovery 45.5 g; m.p. 92.593.5.

Analysis for C H N OS Calc'd.: c. 56.9 H, 9.06; N. 13.99 Found: c,57.32; H. 9.06: N. 14.00 c. 57.34; H. 9.08; N. 14.03

EXAMPLE 3 Bis-(p-nitrobenzyl hydroxylamine) four hours. These was someprecipitate formed which Y was filtered off while hot. The solution wasthen cooled and the product filtered and washed with water. The productweighed about 23 g (slightly moist). On recrystallization from methylcellosolve/water, yellow crystals were obtained 18.4 g melting between159 and 161.

Analysis for C H N O Calcd.: C, 55.44; Found: C, 55.l7;

N. l3.86 N. 1393 EXAMPLE 4 Didodecyl B,/3'hydroxyiminodipropionatel-lydroxylamine hydrochloride (4.0 g) was dissolved in mls. of methanoland the resulting solution was added, at a temperature of 10 to 2.7 g ofsodium methoxide in 50 mls. methanol. A solution of 24.0 g of laurylacrylate in 100 mls. of methanol was added at 5 and the temperature wasallowed to rise slowly. At 15, the reaction was noticeably stronglyexothermic and needed cooling. At the same time, the reaction mixturethickened and 100 mls. of ether was added to keep it mobile. The mixturewas stirred overnight. The solvent was evaporated, the residue takeninto 600 mls. of ether and the organic solution was extracted with aconcentrated sodium chloride solution, dried, filtered and evaporated.The white amorphous residue was recrystallized from alcohol (200-mls.).There was obtained a yield of 18.0 g of product melting between 55 and57.

2-Dodecylamino-4,6-bis-(N-n-propyl-N-hydroxyamino)-s-triazine A solutionof 1 mole of dodecylamine in dioxane was added in about twenty minutesat a temperature of less than 25, maintained with ice bath cooling, to athin slurry of cyanuric chloride in dioxane/water. An aqueous solutionof 1 mole of sodium hydroxide was added thereto rapidly at a temperatureofless than 40 and the reaction mixturewas then poured into a liter ofwater. A light tangummy solid solidified which was filtered, washed withwater and dried under vacuum to constant weight. A yield of 157.0 g(94.5 percent) of product was obtained with a melting point of 6365. Theproduct 2-dodecylamino-4,6-dichloro-s-triazine, was recrystallized fromn-heptane and was obtained in the form of a colorless amorphous productmelting between 64.0 and 65.0".

A dioxane solution of 15.8 g (0.21 mole) of n-propyl hydroxylamine in adioxane solution was added to a slurry of 33.3 grams (0.10 mole) of 2-dodecylamino4,6-dichloro-s-triazine in dioxane over a 30 minute periodat a temperature of less than 5. A sodium hydroxide solution was addedat a temperature of less than 5 until the reaction mixture was slightlyalkaline to phenolphthalein. The solution was warmed at a temperaturebetween 45 and 50 for 1 hour at the end of which time the remainder ofsodium hydroxide solution was added to make a total of 0.20 mole. Thereaction product was filtered at to remove a small amount of colorlesssolid. The light purple filtrate was added to about 1,500 mls. of icecold water. A gummy precipitate was obtained and the material wasdecanted, washed with water and dried under vacuum. The yield of tackypurple solid was 35.0 g (85.4 percent). The product was recrystallizedtwice from nheptane and there was obtained the desired product meltingbetween 915 and 930.

Analysis for C H N O pared, using the procedure described in Example 5above.

A solution of free hydroxylamine was prepared under nitrogen by theaddition, at a temperature of less than 22 of an aqueous solution of1.46 moles of sodium hydroxide to a concentrated aqueous solution of1.60 moles of hydroxylamine hydrochloride. A hot dioxane solution of66.6 g (0.20 moles) of 2-dodecylamino-4,6- dichloro-s-triazine was addedat a temperature of less than 20. The reaction mixture was maintained ata temperature between 55 and for 1 hour and then heated at reflux for 3hours. The cooled reaction mixture was poured into 2 liters of coldwater. There was obtained a gummy solid which hardened on standing. Theyield of crude material was 67.4 g (103 percent), and this material wasrecrystallized once from dioxane and twice from methanol. The meltingpoint of the resulting product was l38.0-l40 (decomposition).

Calcd: c. 55.19; H, 9.36: N, 25.75 Found: c, 55.62: H, 9.44; N, 25.53

EXAMPLE 7 2,4-Bis-(dodecylamino)-6-N-hydroxyamino-s-triazine2,4-Bis-(dodecylamino)-6-chloro-s-triazine was prepared following theprocedure described in Examples 5 and 6 above for the preparation of2-dodecylamino- 4,6-dichloro-s-triazine except that two moles of theamine were used with one mole of cyanuric chloride. The reaction withhydroxylamine was carried out as described, using the procedure ofExample 6 above, ex-

Analysis for C ,H N O Calcd.; C, 6 Found: C, 67.79;

EXAMPLE 8 2-Diethylamino-4,6-bis-( N-n-propyl-N-hydroxyamino)-s-triazineOne mole of aqueous diethylamine was added over a 30 minute period toone mole of cyanuric chloride, at a temperature of 05 in aqueousacetone. Aqueous sodium carbonate solution (0.5 mole) was added in 20minutes at a temperature of 0-5. The slurry was stirred at 05 for 1%hours, and filtered. The filter cake was washed twice with cold water,and dried under vacuum. The yield of colorless crystalline 2-diethylamino-4,6-dichloro-s-triazine was 83.8 g (75.7 percent); meltingpoint 7477. On recrystallization from n-heptane, the melting point wasfound to be between 76.5 and 785.

To a solution of 15.0 g (0.20 mole) of n-propylhydroxylamine in 60millimeters of 1:1 dioxane/water was added, over a 30 minute period at05, a solution of 2-diethylamino-4,6-dichloro-s-triazine in 75 mls. ofdioxane. The mixture was heated at 55-60 for minutes, and refluxed for30 minutes. A solution of 4.0 g (0.10 mole) of sodium hydroxide wasadded, bringing the pH to a slight pink color with phenolphthalein. The

reaction product was refluxed for three hours more and then poured into1 liter of cold water. After standing, the reaction product solidified.This product was filtered, washed with water and then dried. The crudeproduct (13.9 g, 93.3 percent yield) was recrystallized three times frompetroleum ether. The colorless needlesobtained had a melting point of84.086.0.

2,4-Bis-(diethylamino)-6-chloro-s-tria2ine was prepared by the addition,at -5, of 2 moles of an aqueous solution of diethylamine to anacetone-water slurry containing 1 mole of cyanuric chloride. Two molesof sodium hydroxide solution was added at 45-50 while maintaining thealkalinity slightly below the phenolphthalein end point. The resultingoil was separated, dissolved in ether, extracted with water, dried withanhydrous magnesium sulphate, filtered and concentrated to constantweight. There was obtained a 94 percent yield of a liquid product.

To a solution of 15.0 g (0.2 mol) of n-propylhydroxylamine in 60 mls. of1:1 dioxane/water was added in 30 minutes at 0-5, a solution of 25.7 g(0.10 mol) of 2,4-bis-diethylamino-6-chloro-s-triazine in 30 mls. ofdioxane. The mixture was warmed to 55 for 90 minutes and refluxed for 30minutes. The reaction mixture was cooled to 50 and a solution of 4 g(0.1 mol) of sodium hydroxide in 20 mls. of water was added as needed,while maintaining the pH slightly below the red of phenolphthalein.About 24 hours was required for the completion of the reaction period.The reaction mixture was poured into 2 liters of water. The product wasextracted into ether. The ethereal solution was extracted with aqueoushydrochloric acid which was neutralized with aqueous sodium hydroxideliberating the product which was dissolved in ether, washed with water,dried and concentrated at a constant weight. The yield of colorlessliquid product was 20.8 g (70.2 percent yield); n 1.521 l.

Analysis for C H N O Calc'd. C, 56.73; H. 9.52; N, 28.36 Found C, 56.38:H, 8.83; N, 28.20

EXAMPLE 2,4-Bis-(dibutylamino)6-N-hydroxyamino-s-triazine A slurry of 1mole of cyanuric chloride was prepared .in acetone/water and 2 moles ofdibutylamine was Analysis for C H N,O

Calcd and concentrated to constant weight. There was obtained in percentyield 2,4-bis-(dibutylamino)-6- chloro-s-triazine.

Free hydroxylamine was prepared, under nitrogen, by the addition, at atemperature of less than 22, of 1 mole of aqueous sodium hydroxide to1.06 moles of concentrated hydroxylamine hydrochloride solution. To thissolution was added, in a thin stream at a temperature of 26, a solutionof 0.25 moles of the 2,4- bis-(dibutylamino)-4-chloro-s-triazine,prepared by the above procedure, in dioxane. The resulting solution washeated at a temperature of 55 60, for 1 hour. then at reflux for 3.5hours. The mixture was cooled and the reaction product was then added to1 liter of water. The phases were separated. The upper organic phase wasdissolved in ether, washed with water, dried with anhydrous magnesiumsulphate and concentrated to'constant weight under vacuum. The productpartially crystallized on standing. This was followed by slurrying withn-heptane, cooling to 10 and then the mixture was filtered, while cold.The resulting colorless fine needles exhibited a melting point of 78-81,and on recrystallization from methanol/water, the melting point was79.5-8l.5.

Analysis for C H N O Calcd.

c. 62.26; H. 10.45; N, 22.93 Found c, 62.10; H, 10.29; N. 23.20

EXAMPLE 11 3-( N-Propyl-N-hydroxyamino)propionamide c, 49.29; H. 9.65:N. 19.16 Found c. 49.49; H. 9.75- N. 9.14

EXAMPLE l2 B,B'-Hydroxyimino-bis-propionamide Hydroxylaminehydrochloride (28 g) was dissolved in 250 mls. of methanol. Sodiummethylate (21.6 g, 0.4 mol) in 200 mls. of methanol was added at atemperature of O5. Sodium chloride precipitated at this point.Acrylamide (57 g, 0.8 mol) in mls.,of methanol was added at atemperature of 10. No exothermic reaction could be observed at thispoint. The temperature was allowed to rise slowly and the reaction wasexothermic at around 20-25 and reached a maximum of 28. When thetemperature of the reaction mixture 'dropped to about 20, the sodiumchloride was filtered off and the solution was allowed to stand overnight. Crystallization occurred. The crystals were filtered and thenrecrystallized from methanol and dried. A yield of 35.2 g (50.3 percentyield) was obtained. The melting point was l32.5l33.5 (decomposition).

Analysis for C,,H,;,N;,O

Calc'd. C, 41.13; H, 7.48 N. 23.99 Found C, 41.38; H, 7.26 N, 23.87

EXAMPLE 13 N-Propyl-N-(p-chlorobenzyl )-hydroxylamine.

Propyl hydroxylamine (2.6 g, 0.11 mol) was dissolved in 50 mls. of ethylalcohol. p-Chlorobenzyl chloride (17.7 g, 0.11 mol) in 50 mls. of ethylalcohol was added at room temperature. The reaction was noted to beslightly exothermic. Sodium carbonate (5.8 g) in 35 mls. of water wasthen added slowly at -30. A pre' cipitate of sodium bicarbonate wasobtained. The mixture was refluxed for 2 hours and it was noted thatmost of the sodium bicarbonate dissolved. At room temperature, themixture was filtered off and the alcohol evaporated leaving a waxy solidresidue in water. This was extracted with ether and washed with water. Afluffy solid crystallized from the ether (1.5 g). The ether solution wasevaporated leaving behind 17.2 g of a low melting solid. This materialwas dissolved in ether, extracted with dilute hydrochloric acid and theaqueous extract washed with ether. The aqueous solution was neutralizedwith sodium hydroxide, extracted with ether. The ethereal solution waswashed with water, dried and then evaporated. The crude yield of productwas 13.7 g; melting point 48-56. On recrystallization from hexane, ayield of 9.4 g (42.9%) was obtained; melting point 64-66 Analysis for CH NOCl Calcd.

The reaction of 0.1 mole of n-propyl hydroxylamine with 0.1 mole ofpropane sultone was allowed to take place in benzene for 3 days atambient temperature. The benzene was decanted from a colorless viscousliquid product which was concentrated to constant weight under vacuum.The yield of sulfonic acid was 78 percent; the neutral equivalent was220 (theory 197). The acid was converted in aqueous solution to thesodium salt by reaction with an equivalent amount of sodium hydroxide.The aqueous solution was concentrated to dryness. The colorless foamysolid was triturated with benzene, filtered and dried.

Analysis for C H NO SNa Calcd. S. 14.63 Found S. 14.06

EXAMPLE 15 Bis-(3,5-di-t-butyl-4-hydroxybenzyl) Hydroxylamine A solutionof hydroxylamine was prepared under nitrogen by the neutralization of asolution of 28.5 g (0.41 mole) of hydroxylamine hydrochloride in 33 ml.water with 16 g (0.40 mole) of sodium hydroxide in 35 ml water at 20. Tothis solution was added dropwise at 2-6 over 30 minutes a solution of25.5 g (0.10 mole) of 3,5di-t-butyl-4-hydroxybenzyl chloride in ml ofdioxane. The reaction mixture was heated at 5055 for 1 hour and atreflux for 1 hour. The reaction product was evaporated under vacuum toremove dioxane and the residue was extracted with ether. The organicphase was washed with water, dried with anhydrous MgSO and filtered. Theethereal solution was concentrated to dryness. The residue wastriturated with petroleum ether to yield a solid which was recrystallized twice from benzene, m.p. 197.

N 2 Found H. ).77: N.2.

The [R and NMR spectra were in conformance with the structure.

Depending upon the material to be protected and the severity ofoxidation to be encountered, various concentrations of the compounds ofthis invention may be employed as anti-oxidants. Generally, from about0.001 percent by weight of one or more of the active compounds of thepresent invention to about 5 percent is employed. However, in manyinstances, concentrations of anti-oxidant well below the latter figuregive adequate protection. Thus, lubricating oil concentrations of from0.01 to 2 percent by weight of the active compound are usually adequate.Generally it is preferred to use from 0.05 to about 3 percent by weightof the additive compound since it is found that concentrations withinthis range provide adequate anti-oxidant protection.

Although this invention has been described with respect to its preferredembodiments, it should be understood that many variations andmodifications will now be obvious to those skilled in the art, and it ispreferred, therefore, that the scope of the invention be limited not bythe specific disclosure herein, but only by the appended claims.

What is claimed is:

l. The compound propionamide.

1. THE COMPOUND B,B''-HYDROXYIMINO-BIS-PROPIONAMIDE.